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Keywords:

  • instrumentation;
  • sports science

Abstract

  1. Top of page
  2. Abstract
  3. 1. INTRODUCTION
  4. 2. SPECIFIC DEMANDS OF SPORTS SCIENCE
  5. 3. CONCLUSION
  6. REFERENCES

Sport science measurement presents some common and some unique challenges. Common challenges include those of funding, instrumentation availability, size and mass. Unique challenges involve working with celebrity athletes who are often reticent to serve as subjects, coaches who often will not give up training time for measurement, extraordinary demands on ease and speed of measurement and data return, and a different perspective of ‘success’ in conducting research. While the academic scientist's success is usually measured in terms of publications on group data investigations, the sport scientist must improve the specific athlete(s) with whom he/she is working. For example, if an investigation of 20 athletes shows that 15 improved with the intervention, two stayed about the same and three showed worse performance results—statistical significance and/or confidence intervals would likely be achieved and the study would likely meet modern peer review standards. However, if the three athletes who got worse were the three ‘best’ athletes of the group—coaches and the sport scientist will consider the intervention a failure. © 2008 John Wiley and Sons Asia Pte Ltd


1. INTRODUCTION

  1. Top of page
  2. Abstract
  3. 1. INTRODUCTION
  4. 2. SPECIFIC DEMANDS OF SPORTS SCIENCE
  5. 3. CONCLUSION
  6. REFERENCES

Many sports and sports-related institutions and governing bodies conduct sport science on a shoestring budget, while the cost of winning an Olympic medal continually escalates 1,7. Moreover, even when coaches weigh in on the need for sport science in maintaining international competitiveness, the allocation of funds for sport science seems to be lacking in most countries 2,8–10 with a few notable exceptions 3. Of course, one probably never has ‘enough’ money to do everything one wants. The situation is further complicated by the fact that elite athletes and coaches typically resist investigations that steal training time or disrupt training structure. As such, it is rewarding to find means and methods of doing valuable work without extraordinary expense, and often on a few hours notice of a training and/or performance question. The purpose of this paper is to describe some of the inherent problems involved in testing elite athletes.

What is a ‘sport scientist’ and why are their problems different?

By ‘sport scientist,’ I am referring to someone who does the majority of his/her work directly with sports, not with students. Although many sport center and academic laboratories are blessed with large budgets, large staff numbers, and engineers to build testing and performance equipment, many are not 3,10. Moreover, if one simply trends the changes in computers, software compatibility and capability, sensor size, and interfacing, there appears to be a global conspiracy to make sport science investigations as difficult and frustrating as possible. Simply keeping up with operating system changes, presence/absence of serial and parallel connectors for interfacing, computer bus configurations, and so forth can be staggeringly expensive. Sadly, one is often forced to ‘upgrade’ a system that is working perfectly only because of changes in computer architectures or operating systems.

In some ways, the problems of the sport scientist are little different from those in academic or other settings. One can sympathize that academic scientists who work with sport along with exercise may desperately need new instrumentation to prevent the ‘grant or perish’ problem which seems to have replaced the ‘publish or perish’ edict of earlier generations. However, there are real differences between exercise scientists and sport scientists 11, and this paper will attempt to discuss problems peculiar to sport science, and thus sport technology at the highest Olympic levels.

2. SPECIFIC DEMANDS OF SPORTS SCIENCE

  1. Top of page
  2. Abstract
  3. 1. INTRODUCTION
  4. 2. SPECIFIC DEMANDS OF SPORTS SCIENCE
  5. 3. CONCLUSION
  6. REFERENCES

Anyone who has worked with elite athletes, defined as the top eight in the world 12, knows that instrumentation must be nearly invisible to these athletes. Moreover, many coaches of these athletes are utterly intolerant to disturbances to training time or structure simply because a scientist wants to get some data. Even questions developed by coaches have to reach a high level of interest before they will permit scientific intrusions. For example, we often get requests from graduate students who would like to ‘borrow’ some elite athletes for a test that has no chance of improving the athletes they want to test. It is difficult to convince these well-meaning students that the athletes are not there to help them with their thesis or dissertation. Even worse, the scientist who has a good relationship with elite athletes can almost never guarantee that the data collection and subsequent analysis will make the athlete better. An uneasy peace is often struck between scientist, coach, and athlete by testing quickly, disturbing training as little as possible, and demonstrating how these data may improve the athletes being tested.

However, most athletes and coaches will agree that one cannot improve something if one does not measure it. The coach uses his/her well-trained eye to perform a qualitative analysis of movement all the time. Unfortunately, the coach's eye cannot preserve the image for long, show it to someone else, perform calculations on it, or know when the eye has been deceived. In particular, elite athletes often need better instrumentation than the coach's eye. Interestingly, the application of sophisticated instrumentation to the athlete's performance often results in even greater reliance on the coach's judgment. It is important that scientists treat the athlete, something to which the coach is experienced, and not the monitor, gage, video, sensor, and/or data 4–6. However, data are the currency of the sport scientist, and like fine jewels, the quantity and quality of data set the scientist's ability to help the coach and athlete enhance performance. Data usually come from instrumentation.

Thus the modern sports scientist needs instrumentation generally in four major areas: (i) instrumentation the athlete wears in order to obtain data regarding physiological or position information; (ii) instrumentation that connects to, or substitutes for, equipment the athlete uses (i.e. plays with, strikes, runs on, and throws); (iii) instrumentation to record relevant images of the athlete's performance; and (iv) the support instrumentation and equipment that allow all of these things to work, such as power supplies, computers, transmitters, receivers, storage devices, and others.

2.1. Wearing it

Instrumentation to be worn must be extremely light and able to take punishment. Military applications for data collection are usually well designed for ruggedness and use in harsh environments, but may not be available for non-military use and are often cost prohibitive if the instrument is available. Experience has shown that while a male gymnast can handle an electromyography (EMG) transmitter easily in a belt pack 13, the belt pack and EMG transmitter may be a substantial percentage of the weight of a preadolescent 27 kg female gymnast (if you can find a belt that will fit) 14. The instrumentation cannot be so heavy that the athlete must alter technique to accommodate the instrument or compromise safety. We have aborted test trials with worn instrumentation simply because the young athlete was too small to handle the device. As another example, obtaining heart rates using traditional chest strap transmitters and wrist watch receivers has been difficult with athletes who are lean and raise their arms overhead. The chest straps simply fall to their waists. Taping a chest strap to a hairy-chested male athlete is not a comfortable experience for the athlete.

Metabolic equipment has become ‘portable’ in recent years with a processor unit and a power supply placed in a variation of a halter. Hoses, masks, and heart sensors have been built to come from this compact unit. However, this type of unit is usually only useful with runners, cyclists, rowers, and kayakers. This is not a big surprise since these are predominantly aerobic athletes in need of metabolic measurements, but once you move away from these types of sports, metabolic measurements become more difficult. Following a boxer, wrestler, figure skater, martial artist, and so forth through training or a simulated match becomes difficult/impossible due to safety, instrument constraints, and simple entanglement.

The instruments must also be able to take punishment. Athletes fall, compete in freezing and hot temperatures, run and cycle long distances, bump into people, perform in water, sweat, and generally find ways to destroy instrumentation. Doing EMG on an athlete who is seated in an air-conditioned laboratory is relatively easy; doing the same EMG in high heat and humidity is sometimes impossible: the electrodes simply will not stick. For example, a track cyclist who failed to follow instructions and swung his belt pack so violently during pedaling caused the instrumentation to fly out and land on the velodrome track while the cables wrapped around his rear axle (Fig. 1).

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Figure 1. Track cycling athlete with a data logger, electromyography (EMG), and cables in a belt pack. Shortly after this picture was taken, the instrumentation was found around the velodrome. Synchronization with video was obtained by simultaneous starting of recording and timers.

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2.2. Using it

Any athlete who uses a principal piece of equipment to compete could likely profit from knowing how the equipment behaves during use and how his/her actions influence the equipment. For example, tennis rackets, guns, helmets, gloves, cleats, shot puts, bobsleds, skis, snowboards, skates, swords, balls of all types, javelins, starting blocks, bicycle tires, bicycle seats, boats, oars, paddles, and many other objects are used by athletes in order to compete. Most athletes spend enormous amounts of money on training and competition equipment. Simply instrumenting a kayak paddle and then testing an athlete with it will not duplicate the actions of the athlete using his/her own paddle. Not only is the size of the equipment important, but the elasticity, mass distribution, padding, and even the sound the equipment makes can influence an athlete's performance. Most elite athletes have a jaundiced view of trying to perform a well-learned skill for a scientist that uses equipment to which they are unaccustomed. Therefore, athletes are tested with their own bikes, boats, canoes, boats, bows, guns, skis, poles, skates, helmets, and so forth (Fig. 2).

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Figure 2. This device is clamped around the kayaker's own paddle to detect handle flexion in two dimensions.

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The net result is that the idiosyncratic nature of the sport and the athlete's equipment must be preserved while testing is performed. The athlete must use his/her skis, skates, paddle, gloves, and so forth. This puts a premium on designing small sensors that can be attached to the athlete's gear while remaining nearly invisible and weightless; not to mention that the instrument needs to measure the variable of interest. Vision-testing equipment is particularly delicate when used in actual play and must not endanger the athlete's eyes if the equipment is struck.

Simulators have been designed for athlete performance practice and measurement for some time. Rowers are fond of criticizing ergometer measurements because the ergometer ‘does not float’. Simulators have continued to improve in their realism, but are often astonishingly expensive and difficult to develop and implement. Nearly any perceived flaw by the athletes may bring the entire project to a halt because they ‘do not trust it’.

These types of instrumentation are very often custom built and require extraordinary engineering know how. While many brilliant approaches have been used, the time involved and expense often compromise the intended benefits.

2.3. Athlete imaging

The common video camcorder has become so ubiquitous in sport settings that nearly every coach carries one. The advent of digital camcorders, the movement passed tape to recording to memory devices, and the sometimes startling reduction in size of recording instruments have made video recording (no longer ‘taping’) of performances extremely common. So common in fact that it is now difficult to get network television permission to video record performances even if one is doing it only for scientific purposes. Long and painstaking permissions are usually required and often refused if the camera will disturb the director's ‘visual scene’. Moreover, casual camcorders are commonly confiscated at competitions where network television is present.

However, the most important aspect of video recording in terms of sport science lies in either high-speed video for kinematic analysis or in simultaneous video and data capture (or both). The benefits and liabilities of high-speed video are beyond the intent of this paper, but the unification of data with video is well within the reach of sport and is now built into some video analysis software packages 15. Many times, the only reasonable means of getting data without encumbering the athlete and training is to simply video record the performance and conduct a kinematic analysis of the movement in question. Of course, the definition of kinematics (description of motion) means that the sources of motion (i.e. forces, EMG, heart rhythms, and oxygen uptake) may not be known. Kinematic analyses nearly always require a 3-D approach and thus increase complexity, time, and access difficulty; they sometimes require too much time for analysis and data return. In more modest terms, one should currently not consider a data collection project (e.g. forces and EMG) completed unless simultaneous video is involved. The athlete and coach are no longer satisfied, nor in some cases savvy enough, to understand a graph or table of data by itself. They want to see what the performance looked like that produced the data. Prototyping and pilot testing still permits data from sensors without accompanying video, but generally this is for scientific consumption only, not for coaches and athletes.

There remains a place for imaging for the sake of itself. A thermal image of a bobsled on the Lake Placid (NY, USA) track is shown in Figure 3. Note that the runners leave an easily perceptible path in the ice that is invisible to the naked eye.

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Figure 3. Thermal image of a bobsled moving from left to right. Note the runner tracks left by the sled. These tracks can be used to assess the path of the bobsled.

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2.4. Instrumentation support

Winter sports, aquatic sports, and sports that cover great distances remain among the greatest challenges for data collection. Alpine skiing alone can bring sport science to a halt because of changing snow conditions, changing weather, freezing temperatures, long distances, and access to areas where even a handheld camcorder could be useful, but may be restricted. These problems are coupled with having to put a person out in the freezing cold for hours at a time. Experience has shown that metabolic hoses can freeze from the moisture in exhaled air; electronic circuits that work fine in the lab will only work with a small iron-based chemical heat pack (designed for cold hands and feet, costing less than a dollar) tucked into the circuit box that timed an Olympic winter event. Tripods placed on a grass surface for track and field sank slowly and imperceptibly into the soft dirt during the duration of video recording creating an interesting calibration problem during analysis.

Power supplies are a major problem due to excess weight. Grounding, as always, surfaces whenever biological signals are to be obtained along with signals from other sensors. Instrumentation size has already been mentioned, but beyond that, placing instruments in areas where the transmitted signals may be intercepted may violate athletes' rights to privacy. Even the interference from network television can render some instruments useless.

Generators can provide regular electricity, but if one has to lug one up a ski slope along with extra gasoline, the data had better be good. Noise factors alone can be enough to limit the use of generators. Lighting for high-speed video indoors has popped our circuit breakers dozens of times. Recent advances in high-speed video and stepping back to black and white can permit astonishingly good images in simple room light at 500 frames per second.

3. CONCLUSION

  1. Top of page
  2. Abstract
  3. 1. INTRODUCTION
  4. 2. SPECIFIC DEMANDS OF SPORTS SCIENCE
  5. 3. CONCLUSION
  6. REFERENCES

Studying elite athletes is one of the most rewarding and difficult investigations one can undertake. These research subjects are by definition extraordinarily rare. Thus the investigator is dealing with low statistical power and little interest in generalizing to a population; one is often studying the population. Finally, it is difficult to account for athlete performance variability, current fitness status, willingness to be tested, willingness to give a ‘best attempt,’ period of the training plan, and other factors from problems inherent in wearing unusual and unfamiliar equipment, being critically observed by scientists, and the varying importance test results may have on the athlete's career. While the scientist may see the test results as something only to determine status, the coach and athlete may see the results as a means of selection thus producing a tension that was not intended by the scientist.

REFERENCES

  1. Top of page
  2. Abstract
  3. 1. INTRODUCTION
  4. 2. SPECIFIC DEMANDS OF SPORTS SCIENCE
  5. 3. CONCLUSION
  6. REFERENCES
  • 1
    Bernard AB, Busse MR. Who Wins the Olympic Games: Economic Resources and Medal Totals. National Bureau of Economic Research: Dartmouth University, Dartmouth, MA, 2002.
  • 2
    Blimkie CJR, Botterill C. Report on the survey of national sport governing bodies' sport science needs. Canadian Journal of Applied Sport Sciences 1979; 4(3): 230234.
  • 3
    Bloomfield J. Australia's Sporting Success. University of New South Wales: Sydney, Australia, 2003.
  • 4
    Dick F. Winners are made—not born. New Studies in Athletics 1992; 7(3): 1317.
  • 5
    Douge B. A review of coaching effectiveness literature 1988–1992. In reaching for the top. Australian Council for Health, Physical Education and Recreation: Adelaide, Australia, 1993.
  • 6
    Gilbert D. The Miracle Machine. Coward, McCann & Geoghegan: NY, 1980.
  • 7
    Hogan K, Norton K. The price of Olympic gold. Journal of Science and Medicine in Sport 2000; 3: 203218.
  • 8
    Sands WA. Survey of coaches–sport science and education. Technique 1990; 10(1): 56.
  • 9
    Smith D, Norris S. Building a sport science program. Coaches Report 2000; 6(4): 1921.
  • 10
    Stone MH, Sands WA, Stone ME. The downfall of sport science in the United States. Strength and Conditioning Journal 2004; 26(2): 7275.
  • 11
    Stone MH, Stone ME, Sands WA. The downfall of sport science in the United States. Olympic Coach 2005; 17(4): 2124.
  • 12
    Kearney JT. Sport performance enhancement. Design and analysis of research. Medicine & Science in Sports & Exercise 1999; 31(5): 755756.
  • 13
    Sands WA, Dunlavy JK, Smith SL, Stone MH, McNeal JR. Understanding and training the Maltese. Technique 2006; 26(5): 69.
  • 14
    McNeal JR, Sands WA, Shultz BB. Muscle activation characteristics of tumbling take offs. Sports Biomechanics 2007; 6(3): 375390.
  • 15
    Wilson BD. Development in video technology for coaching. Sports Technology 2000; 1: 3440. DOI: 10.1002/jst.9.